﻿namespace ComTools.Map
{
    using System;
    using System.Drawing;
    using System.Drawing.Drawing2D;
    using System.Drawing.Imaging;
    using System.Globalization;
    using System.IO;
    using System.Web;

    /// <summary>
    /// 媒体资源上传
    /// </summary>
    public static class MediaHelper
    {
        /// <summary>
        /// 图片上传（带有无损压缩）
        /// </summary>
        /// <param name="Request"></param>
        /// <param name="imgUrl">图片地址</param>
        /// <param name="dWidth">新生成后的宽度</param>
        /// <param name="dHeight"></param>
        /// <returns>处理结果</returns>
        public static string UpLoad(HttpRequest Request, string imgUrl, int dWidth, int dHeight)
        {
            int maxSize = 1000000;
            HttpPostedFile item = Request.Files[0];

            String saveUrl = imgUrl;
            String fileName = item.FileName;

            String fileExt = Path.GetExtension(fileName).ToLower();

            if (item.InputStream == null || item.InputStream.Length > maxSize)
            {
                throw new AggregateException("上传文件大小超过限制。");
            }
            //创建文件夹
            var t = HttpContext.Current.Server.MapPath(saveUrl);
            if (!Directory.Exists(t))
            {
                Directory.CreateDirectory(t);
            }
            String ymd = DateTime.Now.ToString("yyyyMMdd", DateTimeFormatInfo.InvariantInfo);
            t += ymd + "/";
            if (!Directory.Exists(t))
            {
                Directory.CreateDirectory(t);
            }

            String newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt;

            String filePath = t + newFileName;
            try
            {
                item.SaveAs(filePath);
                return ymd + "/" + newFileName;
            }
            catch
            {
                return string.Empty; ;
            }
        }
        /// <summary>
        /// 无损压缩图片
        /// </summary>
        /// <param name="sFile">原图片</param>
        /// <param name="dFile">压缩后保存位置</param>
        /// <param name="dHeight">高度</param>
        /// <param name="dWidth"></param>
        /// <param name="flag">压缩质量 1-100</param>
        /// <returns>处理结果</returns>
        private static bool GetPicThumbnail(string sFile, string dFile, int dHeight, int dWidth, int flag)
        {
            Image iSource = Image.FromFile(sFile);
            ImageFormat tFormat = iSource.RawFormat;
            int sW = 0, sH = 0;

            //按比例缩放
            Size tem_size = new Size(iSource.Width, iSource.Height);
            if (tem_size.Width > dHeight || tem_size.Width > dWidth) //将**改成c#中的或者操作符号
            {
                if ((tem_size.Width * dHeight) > (tem_size.Height * dWidth))
                {
                    sW = dWidth;
                    sH = (dWidth * tem_size.Height) / tem_size.Width;
                }
                else
                {
                    sH = dHeight;
                    sW = (tem_size.Width * dHeight) / tem_size.Height;
                }
            }
            else
            {
                sW = tem_size.Width;
                sH = tem_size.Height;
            }
            Bitmap ob = new Bitmap(dWidth, dHeight);
            Graphics g = Graphics.FromImage(ob);
            g.Clear(Color.WhiteSmoke);
            g.CompositingQuality = CompositingQuality.HighQuality;
            g.SmoothingMode = SmoothingMode.HighQuality;
            g.InterpolationMode = InterpolationMode.HighQualityBicubic;
            g.DrawImage(iSource, new Rectangle((dWidth - sW) / 2, (dHeight - sH) / 2, sW, sH), 0, 0, iSource.Width, iSource.Height, GraphicsUnit.Pixel);
            g.Dispose();

            //以下代码为保存图片时，设置压缩质量
            EncoderParameters ep = new EncoderParameters();
            long[] qy = new long[1];
            qy[0] = flag;//设置压缩的比例1-100
            EncoderParameter eParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qy);
            ep.Param[0] = eParam;
            try
            {
                ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
                ImageCodecInfo jpegICIinfo = null;
                for (int x = 0; x < arrayICI.Length; x++)
                {
                    if (arrayICI[x].FormatDescription.Equals("JPEG"))
                    {
                        jpegICIinfo = arrayICI[x];
                        break;
                    }
                }
                if (jpegICIinfo != null)
                {
                    ob.Save(dFile, jpegICIinfo, ep);//dFile是压缩后的新路径
                }
                else
                {
                    ob.Save(dFile, tFormat);
                }
                return true;
            }
            catch
            {
                return false;
            }
            finally
            {
                iSource.Dispose();
                ob.Dispose();
            }
        }
    }
}
